<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .container {
            width:500px;
            height:500px;
            background-color:rgba(0,0,0,0.5);
            display:flex;
            flex-direction: row;
            justify-content: center;
            align-items: center;
        }
        .box1{
            width:100px;
            height:100px;
            background-color:red;
            flex:2;
        }
        .box2{
            width:100px;
            height: 100px;
            background-color: green;
            flex:2;
        }
        .box3{
            width:100px;
            height: 100px;
            background-color: blue;
            flex:1;
        }
        .con{
            width:100%;
            background-color: orange;
        }
        ul{
            list-style: none;
            display:flex;
        }
        .tex{
            background-color: rgba(0,0,0,0.5);
            padding:10px;
            margin-left:20px;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="box1"></div>
        <div class="box2"></div>
        <div class="box3"></div>
    </div>
    <hr>
    <div class="con">
        <ul >
            <li>
                <div class="tex">导航1</div>
            </li>
            <li>
                <div class="tex">导航2</div>
            </li>
            <li>
                <div class="tex">导航3</div>
            </li>
        </ul>
    </div>
</body>
</html>